The requirement of weapon life cycle management promotes the research and development of radar Prognostic and Health Management(PHM) technology. And the maintenance pattern of radar equipment has gradually turned from preventive maintenance and corrective maintenance to Condition-Based Maintenance(CBM). By means of combining big data and PHM technology, the data resource of in-service stage can be integrated with other stages in radar life cycle, such as design, manufacture and after-sales service, etc. The whole life cycle management for radar equipment can be realized thoroughly. A kind of network platform architecture is proposed for radar PHM system based on big data, and a brief introduction on the key technologies is provided.